The Doppler effect explains changes in the length of light waves or sound waves as they move toward you or away from you.

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Similarly, just as we have symbols for the presence of sound and its length, we have symbols that represent the absence of sound.

类似的,既然我们有符号,来表示声音的频率和长度,我们也有表示静音的符号

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It isn't the pitch you need to listen for, but the length of the sound itself.

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The following year, the band released its Words of Sound EP before following it up with the full-length Pontus, the Devil, and Me at the start of 2008.

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Program length will be infinitely variable from hours of non-stop viewing to constantly interrupted sound bites, no longer proscribed by 30 minute increments.

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